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A calix[3]carbazole-based cavitand was conveniently synthesized. It was found that the cavitand with adjustable conformation could show excellent complexation with fullerenes C60 and C70 in both solution and the solid state. Moreover, the crystal structures of the host–guest complexes show that the cavitand can stack into channel-like architectures, in which fullerenes are orderly arranged inside. [ABSTRACT FROM AUTHOR]

Efficient narrow deep‐blue and broadband emissions in layered 2D organic–inorganic hybrid metal halide perovskites (MHPs) are attracting more attention and need further study. In this work, two (100)‐oriented 2D organic‐inorganic hybrid MHPs of (TFI)2PbBr4 and (TFI)2PbCl4·H2O (TFI = 4‐(trifluoromethyl)‐1H‐imidazole) with efficient deep‐blue and bluish‐white emissions are synthesized and the photoluminescence quantum yields (PLQYs) reached up to 81.21% and 20.23%, respectively. As both intrinsic lattice distortions of two crystals with similar crystal structure are almost negligible, they have theoretical deep‐blue emissions empirically. However, the halogen substitution of chlorine (Cl) by bromine (Br) broadened the deep‐blue photoluminescence to a bluish‐white area. Here, the spectral broadening phenomenon is discussed in detail. The (TFI)2PbBr4 film shows a narrow emission with a 16 nm full width at half maximum (FWHM) peaking at 435 nm upon excitation, and an ultraviolet‐pumped light‐emitting diode (LED) prepared by bluish‐white (TFI)2PbCl4·H2O phosphor shows a color rendering index (CRI) of ≈93 and a related color temperature (CCT) of 4162K, indicating their potential applications in deep‐blue and white LEDs, respectively. [ABSTRACT FROM AUTHOR]

A series of the functionalised pillar[5]arene ureidopyrimidinone derivatives were successfully synthesised by the condensation reaction of mono-amido-functionalised pillar[5]arenes with 2-(1-Imidazolylcarbonylamino)-6-methyl-4-pyrimidinone in dry chloroform. 1H NMR, 2D NOESY spectra and single crystal structure clearly indicated that novel [1]rotaxanes were formed by insertion of longer alkylene chain into the cavities of the pillar[5]arenes. On the other hand, the ureidopyrimidinone-functionalised pillar[5]arenes tend to form the dimer in chloroform and in solid state through the self-complementary quadruple hydrogen bonding of the ureidopyrimidinone. [ABSTRACT FROM AUTHOR]

The design and synthesis of crystalline materials have been a subject of intensive research because of their interesting structures, physicochemical properties, and potential applications. However, the crystalline structure of organic–inorganic hybrid materials collapses to lose the structural features of the original networks and/or frameworks when exposed to different stimuli such as pH, vapor, water, high temperature, and organic solvents. This hampers further studies focusing on practical applications. Although several review articles provide reasonable pathways for the preparation of stable metal–organic frameworks (MOFs) and coordination polymers (CPs), the synthesis and design of stable materials containing organic species remain challenging. In this frontier article, we discuss the development of crystalline MOF, CP, metallophosphate, and metallophosphite materials, and provide a feasible approach for the formation of stable organic–inorganic hybrid compounds that combine MOFs (or CPs) and phosphate (or phosphite) building elements. In addition to their interesting structures, the synthetic strategies and structural stabilities of such hybrid composites are also presented. [ABSTRACT FROM AUTHOR]

Replacing methylammonium (MA+), formamidine (FA+), and/or cesium (Cs+) in 3D metal halide perovskites by larger organic cations have built a series of low‐dimensional metal halide perovskites (LDMHPs) in which the inorganic metal halide octahedra arranging in the forms of 2D layers, 1D chains, and 0D points. These LDMHPs exhibit significantly different optoelectronic properties from 3D metal halide perovskites (MHPs) due to their unique quantum confinement effects and large exciton binding energies. In particular, LDMHPs often have excellent broadband luminescence from self‐trapped excitons. Chemical composition, hydrogen bonding, and external factors (temperature and pressure etc.) determine structures and influence photoelectric properties of LDMHPs greatly, and especially it seems that there is no definite regulation to predict the structure and photoelectric properties when a random cation, metal, and halide is chosen to design a LDMHP. Therefore, this review discusses the construction strategies of the recent reported LDMHPs and their application progress in the luminescence field for a better understanding of these factors and a prospect for LDMHPs' development in the future. [ABSTRACT FROM AUTHOR]

An exploratory study of the lead-tellurium-oxygen phase space led to two new compounds, Ba3PbTe6O16 (BPTO) and Na2Pb9(μ6-O)2(Te2O10)2 (NPTO), which were synthesized under hydrothermal conditions at 550 °C and 210 °C, respectively, and characterized by single-crystal X-ray diffraction, infrared and X-ray photoelectron spectroscopy. BPTO adopts a layer structure. The Te4+ cation in BPTO is bonded to four oxygen atoms at about 2.0 Å with two more oxygens at about 3.0 Å. The seesaw-shaped TeO4 units share corners to form 2D layers containing six-membered rings and the Ba2+ and Pb2+ cations are situated in the interlayer region. The structure of NPTO contains dimers of edge-sharing Te6+O6 octahedra, which are connected through five-coordinate Pb2+ cations. A unique six-coordinate O atom is at the center of the octahedron formed by five Pb2+ and one Na+ cations. BPTO is one of the few metal tellurites which were synthesized under supercritical hydrothermal reaction conditions. The Pb2+ cation in NPTO shows pronounced stereochemical effects of the lone electron pair. In contrast, BPTO shows no stereochemical evidence of the inert pair. [ABSTRACT FROM AUTHOR]

An exploratory study of the lead-tellurium-oxygen phase space led to two new compounds, Ba3PbTe6O16 (BPTO) and Na2Pb9(μ6-O)2(Te2O10)2 (NPTO), which were synthesized under hydrothermal conditions at 550 °C and 210 °C, respectively, and characterized by single-crystal X-ray diffraction, infrared and X-ray photoelectron spectroscopy. BPTO adopts a layer structure. The Te4+ cation in BPTO is bonded to four oxygen atoms at about 2.0 Å with two more oxygens at about 3.0 Å. The seesaw-shaped TeO4 units share corners to form 2D layers containing six-membered rings and the Ba2+ and Pb2+ cations are situated in the interlayer region. The structure of NPTO contains dimers of edge-sharing Te6+O6 octahedra, which are connected through five-coordinate Pb2+ cations. A unique six-coordinate O atom is at the center of the octahedron formed by five Pb2+ and one Na+ cations. BPTO is one of the few metal tellurites which were synthesized under supercritical hydrothermal reaction conditions. The Pb2+ cation in NPTO shows pronounced stereochemical effects of the lone electron pair. In contrast, BPTO shows no stereochemical evidence of the inert pair. [ABSTRACT FROM AUTHOR]

An approach to the highly efficient synthesis of C(sp3)‐bridged [6]cycloparaphenylenes (C[6]CPPs) from fluoren[3]arenes (F[3]As) was developed. Consequently, F[3]As as a new kind of macrocyclic arenes were synthesized. Followed by the demethylation, triflation and intramolecular aryl–aryl coupling reactions, C[6]CPPs were then conveniently obtained. Interestingly, C[6]CPPs could be selectively methylated to produce their fully outer‐methyl‐substituted derivatives. The crystal structures showed the hydroxyl‐substituted F[3]As had bowl‐shaped conformations, and the C[6]CPPs exhibited rigid belt‐shaped structures with deep cavities. Moreover, C[6]CPPs exhibited high HOMO energies and narrow energy gaps. An unclosed belt was further obtained, and it not only showed a similar narrow energy gap to those of the aromatic belts, but also displayed strong fluorescence property, which can play a vital role in the design and synthesis of new aromatic belts. [ABSTRACT FROM AUTHOR]

The past 2 decades have witnessed the explosion of research on two-dimensional (2D) materials, where notable efforts have been made in the synthesis and design of a wide spectrum of applications. To understand their mechanical properties and responses triggered by deformation, the prerequisites for reliable applications under realistic service conditions, novel experimental methods have to be developed due to the limitations of traditional bulk mechanical testing for atomically-thin structures. Besides, the nearly-ideal 2D crystalline structures of many 2D materials endow them the great capability of deformation, showing promising potentials in "strain engineering" and "interface engineering" applications. This review summaries several representative approaches in experimental nanomechanics and corresponding progresses in the characterization of structural and mechanical properties of 2D materials, with the aim to provide insights into the instrumental design for nanomechanical tests. In addition, examples of strain-tuned material behaviors and changes in their performance are also discussed to demonstrate the significance of the nanomechanical approach for functional device design and applications. [ABSTRACT FROM AUTHOR]

Poly(L-lactic acid) (PLLA) has drawn much attention due to its excellent medical and pharmaceutical applications for decades. As a semi-crystalline polymer, morphology and crystal structure of PLLA greatly determine its properties. Here, we demonstrate, for PLLA films, a non-conventional texture featuring two types of spherulites emerging in pairs to form a distinct nested structure where a small spherulite (~10 µm) is embedded in a large one (100 µm to 300 µm). In addition to the size, the molecular weight and polymorph are different in the large and small spherulites. Crystallographic α-form and relatively low molecular weight are identified in the large spherulites, while meta-stable α′-form and relatively high molecular weight in the small ones. These differences suggest that the polydisperse PLLA polymers fractionate during film formation and the high-molecular-weight fraction crystallizes into the small spherulites with meta-stable structure because of its complicated polymer entanglement and high viscosity. In contrast, the rest of polymers crystallize into the large spherulites with the thermodynamically stable polymorph. Furthermore, this texture exhibits accelerated PLLA degradation initiated from the small spherulites, which is distinct from the typical PLLA spherulites. Insights provided by this work may lead to new texture-properties relationship associated with polydispersity of molecular weight. [ABSTRACT FROM AUTHOR]

Three standalone tetrahedral copper hydride clusters, [Cu4(μ4-H)(μ2-X)2(PPh2Py)4]+ (X = Cl, Br; Py = pyridyl), containing a tetrahedral [Cu4(μ4-H)] unit have been synthesized and structurally characterized. The six Cu-Cu distances of the [Cu4(μ4-H)] unit can be divided into three groups (2.65, 2.85, and 2.95 Å), lowering the idealized point group of the Cu4 core to D2 symmetry, thereby resulting in intrinsically chiral metal clusters which exist as racemic pairs of enantiomers in the centrosymmetric crystal structures. Strong photoluminescence (attributable to the existence of the two short Cu-Cu distances of 2.65 Å) was observed in solution and in the solid state upon near-UV irradiation. According to the Jellium model, the title clusters can be considered as two-shell Jelliumatic systems with superatomic electron counts of 2e@0e corresponding to the two shells of H−@[Cu4X2(PPh2Py)4]2+. The four-coordinated hydride in the tetrahedral Cu4 cavity adopts the superatomic electronic configuration of 1S2. [ABSTRACT FROM AUTHOR]

A series of functionalized pillar[5]arenes mono-pyridylimine derivatives with different lengths of diaminoalkylene units as the side chains on the pillar[5]arene's rim were conveniently synthesized. The investigation of 1 H NMR spectra and single crystal structures indicated that the formation of free forms or pseudo[1]rotaxanes turned out to be controlled by both the axle lengths of diaminoalkylene chains and the solvent effect. The pillar[5]arene mono-pyridylimines with short hydrazinyl and diaminoethylene chains exist in free form. On the other hand, pillar[5]arene mono-pyridylimines with longer than diaminopropylene chains formed stable pseudo[1]rotaxanes both in solution and in the crystal state. [ABSTRACT FROM AUTHOR]

A series of thiourea-functionalised pillar[5]arene derivatives3nmwere constructed from a series of mono-amide-functionalised pillar[5]arenes2n. The formation of their free forms or (pseudo)[1]rotaxane structures were controlled by their axle lengths or solvents, which were investigated by1H NMR spectroscopy. Some of (pseudo)[1]rotaxane structures were also supported by their single-crystal structures. [ABSTRACT FROM AUTHOR]

One dimensional coordination polymer Gd[(SO 4 )(NO 3 )(C 2 H 6 SO) 2 ] ( 1 ) is prepared through the mediation of Bronsted acid ionic liquid, which crystallized in the monoclinic space of C2/c. In this polymer, adjacent Gd atoms are linked by two SO 4 2- ions to generate a 1-D chain, and all oxygen atoms in SO 4 2- groups are connected to three nearest Gd atoms in µ 3 :η 1 :η 1 :η 2 fashion. Gd, S and N from SO 4 2- and NO 3 - are precisely coplanar. The planar is coordinated by a pair of DMSO molecules, which is parallel and linked by hydrogen bonding to form a three-dimensional supramolecular network. Magnetic susceptibility measurement of 1 reveals weak antiferromagnetic interactions between the Gd (III) ions. It exhibits relatively large magneto-caloric effect with –ΔS m =28.8 J Kg −1 K −1 for ΔH=7 T. [ABSTRACT FROM AUTHOR]

A series of Ca 0.98− x MoO 4 :Dy 3+ 0.02 ,M + x (M = Li, Na, K, 0 ≤ x ≤ 0.16) phosphors were synthesized rapidly using microwave radiation method in 30 min. The effects of doping alkali metal ions on the phase structure and luminescent properties of the phosphors were analyzed using X-ray powder diffraction, scanning electron microscopy, fourier transform infra-red spectroscopy, and fluorescence spectrophotometry. The results confirmed that all the samples were pure tetragonal CaMoO 4 structure. The samples consisted of many cubic particles and some irregular polyhedron particles, assembled by fine spherical-like grains. The main emission peak was located at 574 nm, which was attributed to the 4 F 9/2 → 6 H 13/2 transition of Dy 3+ . The addition of alkali metal ions could effectively improve the intensity of the main emission peak. K + had better improvement on emission intensity than Na + and Li + . For the series of Ca 0.98− x MoO 4 :Dy 3+ 0.02 ,K + x phosphors, the optimum doping content of K + was 0.10 with 2.6 times of the emission intensity at 574 nm of the undoped-K + sample. The color coordinates gradually shifted from yellow-green region to the yellow region with the increasing of K + content (0 ≤ x ≤ 0.10). When x = 0.10, the sample shows the strongest yellow-emitting. [ABSTRACT FROM AUTHOR]

BiOI/HZSM-5 composites were synthesized via a facile and environmentally-benign hydrothermal method. The crystalline structures and morphologies of the powder have been characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic activity of samples was tested for degradation of methylene blue (MB) and Rhodamine B (RhB) dye under simulated solar light irradiation. The degradation rate of MB and RhB by BiOI/HZSM-5 composite photocatalysts respective reach 99.6% and 98.6% under visible light irradiation, BiOI/HZSM-5 exhibited the highest photocatalytic performance when compared with pure BiOI. Flower-like BiOI/HZSM-5 microspheres were obtained using a simple EG-assisted hydrothermal method. The as-obtained BiOI/HZSM-5 samples exhibited excellent performance in the degradation of methylene blue (MB) and Rhodamin B (RhB) dye under simulated solar light irradiation. Moreover, BiOI/HZSM-5 also possesses a high adsorption capacity and excellent stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • The addition of Al increases the nucleation rate of the Cu-rich phase. • The addition of Al can increase the coarsening rate of the Cu-rich phase. • The addition of Al changes the crystal structure of the Cu-rich phase. • The addition of Al hinders the coarsening of the Cu-rich phase into a rod shape. • The Al-containing Cu-rich nanoprecipitates are rich in high-density edge dislocations. In this article, scanning electron microscopy, energy dispersive spectroscopy, and transmission electron microscopy were used to characterize the precipitation behaviour of the Cu-rich phase in Al-free and 1Al Cu-bearing ferrite stainless steels; and further, the effects of Al addition on the precipitation and coarsening of the Cu-rich phase and its mechanism were analysed. The results show that Al increases the nucleation rate of the Cu-rich phase, and refines Cu-rich nanoprecipitates after ageing for 1 min. The Cu-rich phase with four crystal structures-BCC, 9R, twin FCC, and non-twin FCC were found in the Al-free sample during ageing. However, only Cu-rich phase with BCC and BCT structures were observed after Al addition. There are high-density edge dislocations in Al-containing Cu-rich nanoprecipitates. These dislocations can be used as a diffusion channel for solute atoms, increasing the coarsening rate of the Cu-rich phase. However, with the extension of the ageing time, dislocations in the Cu-rich phase will be annihilated owing to the thermal activation and the decrease of the Al concentration in the Cu-rich phase, which will lead to a decrease in the dislocation density in Al-containing Cu-rich phase. Finally, the promotion effect of Al on the coarsening of the Cu-rich phase is weakened. [ABSTRACT FROM AUTHOR]

In this paper, by introducing bisphenol A into rare earth-Eu3+ and 1,10-Phenanthroline, Eu(BPA)Phen complex was prepared by the solvothermal reaction. Then, a novel Eu(BPA)Phen/PA6 fiber with high luminescence efficiency and heat stability was prepared by the melt spinning method successfully. The intermolecular and intramolecular hydrogen bonding, crystalline structure, orientation behavior and surface morphology of Eu(BPA)Phen/PA6 fiber were characterized by FT-IR, XRD and SEM respectively. Meanwhile, rheological behavior, thermal-stability, mechanical performance and photoluminescence properties of Eu(BPA)Phen/PA6 fiber were investigated systematically. It is found that there is a strong hydrogen bonding interaction inside Eu(BPA)Phen/PA6 composite system. The incorporation of Eu(BPA)Phen complex has no effect on the crystalline structure, viscosity and mechanical properties of the Eu(BPA)Phen/PA6 fiber, and these properties are basically the same as the original PA6 fiber. And the Eu(BPA)Phen complex has good dispersibility in the PA6 matrix, and the surface of Eu(BPA)Phen/PA6 fiber is smooth and uniform. Compared with the original Eu(BPA)Phen complex, the photoluminescence efficiency of Eu(BPA)Phen/PA6 fiber increased by about 14 times, and the decomposition temperature of Eu(BPA)Phen/PA6 fiber increases by about 20 °C in the comparation of pure PA6. It means that the prepared Eu(BPA)Phen/PA6 fiber possesses outstanding luminous efficiency and thermal stability without reducing processing and mechanical performance. Thus, it has potential applications in color displays and sensor systems. [Display omitted] • The luminescent PA6/Eu(BPA)Phen fiber was successfully prepared using the melt spinning method. • Compared with the Eu(BPA)Phen complex, the photoluminescence efficiency of Eu(BPA)Phen/PA6 fiber rises by about 14 times. • The thermal decomposition temperature of PA6/Eu(BPA)Phen fiber reaches 420 °C. [ABSTRACT FROM AUTHOR]

Understanding the HIV integrase protein and mechanisms of resistance to HIV integrase inhibitors is complicated by the lack of a full length HIV integrase crystal structure. Moreover, a lentiviral integrase structure with co-crystallised DNA has not been described. For these reasons, we have developed a structural method that utilizes free software to create quaternary HIV integrase homology models, based partially on available full-length prototype foamy virus integrase structures as well as several structures of truncated HIV integrase. We have tested the utility of these models in screening of small anti-integrase compounds using randomly selected molecules from the ZINC database as well as a well characterized IN:DNA binding inhibitor, FZ41, and a putative IN:DNA binding inhibitor, HDS1. Docking studies showed that the ZINC compounds that had the best binding energies bound at the IN:IN dimer interface and that the FZ41 and HDS1 compounds docked at approximately the same location in integrase, i.e. behind the DNA binding domain, although there is some overlap with the IN:IN dimer interface to which the ZINC compounds bind. Thus, we have revealed two possible locations in integrase that could potentially be targeted by allosteric integrase inhibitors, that are distinct from the binding sites of other allosteric molecules such as LEDGF inhibitors. Virological and biochemical studies confirmed that HDS1 and FZ41 share a similar activity profile and that both can inhibit each of integrase and reverse transcriptase activities. The inhibitory mechanism of HDS1 for HIV integrase seems to be at the DNA binding step and not at either of the strand transfer or 3' processing steps of the integrase reaction. Furthermore, HDS1 does not directly interact with DNA. The modeling and docking methodology described here will be useful for future screening of integrase inhibitors as well as for the generation of models for the study of integrase drug resistance. [ABSTRACT FROM AUTHOR]

10α,20α-di(4-aminophenyl)calix[4]pyrroles were synthesized from the acid catalyzed cyclization of dialkyldipyrromethanes with p -nitroacetophenone and sequential hydrogenation of nitro group, which in turn reacted with several aromatic aldehydes and pyridinecarboxaldehydes as well as isocyanates to give a series of calix[4]pyrrole 10α,20α-disubstituted Schiff base and urea derivatives. The crystal structures of the newly-formed calix[4]pyrrole Schiff bases were successfully determined by X-ray diffraction. The complexing property of calix[4]pyrrole Schiff bases for transition metal ions was also investigated with UV–Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: In the presence of methanesulfonic acid as catalyst, the condensation reactions of 5,5′-dialkyldipyrromethanes with p-hydroxyacetophenone in methanol resulted in a mixture of the unexpected polysubstituted 15α,20α-di(4-hydroxylphenyl)calix[4]pyrroles and the expected 10α,20β-di(4-hydroxylphenyl)calix[4]pyrroles in comparable lower yields. The crystal structures of the new calix[4]pyrroles and their oxyacetate derivatives were successfully determined by X-ray diffraction and the intermolecular interactions in the solid state is briefly discussed. [Copyright &y& Elsevier]

Abstract: Treatment of binuclear complex [Cp*2Ir2(μ-dhaq)Cl2] (H2dhaq = 1,5-dihydroxy-9,10-anthraquinone) with pyrazine or bifuncational pyridyl-based ligands (4,4′-bipyridine (bpy), E-1,2-bis(4′-pyridyl)ethene (bpe), and 2,5-bis(4′-pyridyl)- 1,3,4-oxadiazole (bpo)) in the presence of AgOTf (OTf = CF3SO3) in CH3OH, gave the corresponding tetranuclear complexes, with a general formula of [Cp*4Ir4(μ-dhaq)2(μ-L)2](OTf)4 (2a–2d), respectively. The molecular structure of [Cp*4Ir4(μ-dhaq)2(μ-pyrazine)2](OTf)4 (2a) has been determined by single-crystal X-ray analysis, revealing that the metal centers were connected by pyrazine and bis-bidentate dhaq2− ligands to construct a “slope” rectangular cavity with the dimension of 7.4 × 8.8 × 6.9 Å. 2a also exhibited unique properties in host–guest behavior. [Copyright &y& Elsevier]

Peroxisome proliferator-activated receptor gamma (PPARγ) regulates metabolic homeostasis and is a molecular target for anti-diabetic drugs. We report here the identification of a steroid receptor ligand, RU-486, as an unexpected PPARγ agonist, thereby uncovering a novel signaling route for this steroid drug. Similar to rosiglitazone, RU-486 modulates the expression of key PPARγ target genes and promotes adipocyte differentiation, but with a lower adipogenic activity. Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for RU-486 in the PPARγ ligand-binding pocket with distinctive properties and epitopes, providing the molecular mechanisms for the discrimination of RU-486 from thiazolidinediones (TZDs) drugs. Our findings together indicate that steroid compounds may represent an alternative approach for designing non-TZD PPARγ ligands in the treatment of insulin resistance. [ABSTRACT FROM AUTHOR]

Soft magnetic Fe 72.7 Al 0.8 Si 17.5 B 5 Cu 1 Nb 3- x Ge x ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) amorphous alloys were produced by the single roller melt spinning method. The effects of Ge substitution for Nb on the microstructure and magnetic properties were investigated. Magnetic properties of all the alloys annealed at different temperatures were measured by the temperature dependence of initial permeability ( μ i - T curves) from the ambient temperature up to 650 ° C. Structure and crystalline process have been analyzed by XRD patterns and DSC curves, respectively. Partial substitution of Nb by Ge enhanced the Curie temperatures of amorphous phase and crystalline phase, and therefore improved the soft magnetic properties at high temperature. The Fe 72.7 Al 0.8 Si 17.5 B 5 Cu 1 Nb 2.6 Ge 0.4 alloy annealed at 570 ° C for 0.5 h shows the optimum high-temperature μ i , together with higher room-temperature μ i . The origin of the improved magnetic softness both at room- and high-temperature was analyzed. [ABSTRACT FROM AUTHOR]

In this study, we report the structure and function of a lectin from the sea mollusk Crenomytilus grayanus collected from the sublittoral zone of Peter the Great Bay of the Sea of Japan. The crystal structure of C. grayanus lectin (CGL) was solved to a resolution of 1.08 Å, revealing a β-trefoil fold that dimerizes into a dumbbell-shaped quaternary structure. Analysis of the crystal CGL structures bound to galactose, galactosamine, and globotriose Gb3 indicated that each CGL can bind three ligands through a carbohydrate-binding motif involving an extensive histidine- and water-mediated hydrogen bond network. CGL binding to Gb3 is further enhanced by additional side-chain-mediated hydrogen bonds in each of the three ligand-binding sites. NMR titrations revealed that the three binding sites have distinct microscopic affinities toward galactose and galactosamine. Cell viability assays showed that CGL recognizes Gb3 on the surface of breast cancer cells, leading to cell death. Our findings suggest the use of this lectin in cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Luminescent and lead‐free organic‐transition metal halides (OTMHs) are greatly interesting for optical applications. In this work, six single crystals of pyrrolidinium manganese halides are prepared (C4H10N)MnCl3 (1), (C4H10N)8(Mn2Cl10)(MnCl4) (2), (C4H10N)MnBr3 (3), (C4H10N)2MnBr4 (4), and (C4H10N)2MnI4 (5 and 6 with two different crystal configurations). The analysis of crystal structures illustrates that halide ions play an important role in the crystal structure and further affect the luminescent properties of pyrrolidinium manganese halides. It is only for Cl− and Br− that produce perovskite‐type crystals which exhibit red emission. Other crystals with MnX42− tetrahedron unit emit green or yellow lights. It is interesting that the obtained crystals only contain one kind of halide ion with higher atomic number if there are two kinds of halide ions existing in the crystal growth solution. This study illustrates that the luminescent properties of OTMHs can be tuned by halide ions through deliberately designing experiments. The luminescent single crystals of pyrrolidinium manganese halides are grown in solution. The analysis of crystal structures shows that halide ions greatly affect the crystal structures which determine the luminescent properties of crystals. Thus, the emission of pyrrolidinium manganese halide crystals can be tuned from green to red by altering halide ions. [ABSTRACT FROM AUTHOR]

Abstract Three new coordination polymers [Co(L)(1,2,4,5-BTC) 0.5 (H 2 O)] n (1), {[Ni(L)(1,2-BDC)(H 2 O) 3 ]·H 2 O} n (2) and {[Zn 3 (L) 2 (1,3,5-BTC) 2 (H 2 O) 2 ]·3H 2 O} n (3) [ L = 3,6-bis(imidazole-1-yl)pyridazine, H 4 BTC = 1,2,4,5-Benzenetetracarboxylic acid, H 2 BDC = 1,2-Benzenedicarboxylic acid, H 3 BTC = 1,3,5-Benzenetricarboxylic acid] were synthesized based on a rigid ligand L and different aromatic carboxylic acid ligands under solvothermal conditions. The structures of the complexes 1–3 were determined by single crystal X-ray diffraction and further characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). In addition, UV–vis diffuse-reflectance spectra demonstrate wide band gaps. The structural analysis reveals that complex 1 features a two-dimensional (2D) layer structure with a 6-connected sql topological net. Complex 2 shows a one-dimensional (1D) zigzag chain, while complex 3 displays a three-dimensional (3D) coordination network which exhibits an intriguing (5,5,6)-connected novel topological net with the point symbol of {32·42·53·63} 2 {32·44·54·63·72}. Moreover, the luminescence property and lifetimes of complex 3 has been measured at room temperature. Furthermore, in the complex-catalyzed homocoupling reaction of 4-substituted aryl iodides, the catalytic activities of complexes 1–3 have also been studied and discussed. Graphical abstract Three new coordination polymers were synthesized based on 3,6-bis(imidazole-1-yl)pyridazine and different aromatic carboxylic acid ligands. Complex 1 features a two-dimensional (2D) layer structure with a 6-connected sql topological net, 2 shows a one-dimensional (1D) zigzag chain, while complex 3 displays a three-dimensional (3D) coordination network which exhibits an intriguing (5,5,6)-connected novel topological net with the point symbol of {32·42·53·63} 2 {32·44·54·63·72}. Furthermore, in the complex-catalyzed homocoupling reaction of 4-substituted aryl iodides, the catalytic activities of complexes 1–3 have also been studied and discussed. Image 1 Highlights • 3,6-bis(imidazole-1-yl)pyridazine. • Mixed-ligand complexes. • Structural analysis of all complexes. • Complex-catalyzed homocoupling reaction. [ABSTRACT FROM AUTHOR]

Four new complexes [Ni 3 ( L 1 ) 3 (H 2 O) 10 ] ( 1 ), [Zn 3 ( L 2 ) 3 (H 2 O)] n ( 2 ), [Cd( L 2 )(H 2 O)] n ( 3 ) and [Cd 2 (H L 2 ) 4 (H 2 O) 4 ] ( 4 ) have been synthesized by the reaction of 4-(1 H -tetrazol-5-yl)phenol (H 2 L 1 ) and 2-(1 H -tetrazol-5-yl)phenol (H 2 L 2 ) with nickel, zinc, cadmium salts. Complex 1 was synthesized by H 2 L 1 ligand at room temperature conditions, 2 and 3 are synthesized by H 2 L 2 ligand in situ reaction under hydrothermal conditions, 4 is synthesized by H 2 L 2 ligand at room temperature reflux conditions. All of them were characterized by elemental analysis and single-crystal X-ray diffraction, infrared spectrosopy, powder X-ray diffraction and thermogravimetric analysis (TGA). Complexes 1 and 4 are the small-size clusters, the structure of complexes 2 and 3 reveal 2D coordination network. Topologically, complexes 2 and 3 show that binodal networks with a 4-connected and the point symbol of (4 4 ·6 2 ). In addition, magnetic, fluorescence, and UV–Vis properties of these complexes have been studied. [ABSTRACT FROM AUTHOR]

Semiconductor SnC 2 O 4 powders with novel butterfly-like shape were synthesized by the one-step precipitation method. XRD, SEM, UV–vis DRS, PL, BET and FTIR were used to characterize the SnC 2 O 4 samples. The results indicate that the samples obtained at different reaction time are all pure monoclinic phase SnC 2 O 4 with butterfly-like shape. The formation mechanism was proposed on the basis of intrinsic crystal structure and synthesis time. The average band gap is estimated to be 3.33 eV.The PL spectrum suggests that the SnC 2 O 4 samples might have a large number of oxygen vacancies and some other defects. The photocatalytic activity of SnC 2 O 4 was investigated using Acid Red B and Methyl Orange as simulated dye wastewater. For 40 mg/L Acid Red B and MO, the degradation rate can reach to 96.5% and 96.4% under ultraviolet light, respectively. The corresponding reaction kinetics was explored. Furthermore, the degradation mechanism of the dye was explored by introducing the scavengers of active species and comparing with active carbon. The results show that ·OH as well as ⋅ O 2 − play a dominant role of the dye. Recycling test indicates that as-synthesized SnC 2 O 4 was stable in five cycles. [ABSTRACT FROM AUTHOR]